Electrical connector



4 Speets-Sheet 1 INVENTOR.

GEORGE J. SWANSON BY R YS G. J. swANsoN ELECTRICAL CONNECTOR ATTO March17, 1964 Filed April 24, 1959 Mardl 1 1964 G. J. SWANSON ELECTRICALCONNECTOR Filed April 24, 1959 4 Sheets-Sheet 2 INVENTOR GEORGE J.SWANSON BY g j.

ATTOR' YS March 17, 1964 G. J. SWANSON 3,125,395

ELECTRICAL CONNECTOR Filed April 24, 1959 4 Sheets-Sheet 3 INVENTOGEORGE J. SWANS ATTO v EYS I March 17, 1964 G. J. swANsoN 3,125,395

ELECTRICAL CONNECTOR Filed April 24, 1959 4 Sheets-Sheet 4 INVENTCR.

GEORGE J. SWANSON Jf ATTOR EYS United States Patent 3,125,395 ELECTRICALCONNECTOR George J. Swanson, Sidney, N.Y., assignor to The BendixCorporation, a corporation of Delaware Filed Apr. 24, 1959, Ser. No.808,611 18 Claims. (Cl. 339-176) This invention relates to electricalconnectors, and particularly relates to a device for separablyconnecting electrical conductors such as wires, cables and the like.

The invention has among its objects the provision of a novel electricalconnector of the pin and socket type.

A further object of the invention lies in the provision of a separableconnector of the above indicated type, one or both of the connectorparts having cooperating novel means for retaining the contacts in aninsulating insert within the connector shell.

Still a further object of the invention lies in the provision, in asepanable connector of the type indicated, of an improvedcontact-retaining means of such construction that a contact may beinserted into the connector part in fully operative position therein,after the contact has been connected to its conductor or wire, by asimple manipulation consisting essentially of thrusting the thusconnected contact and wire axially into the connector part.

Yet another object of the invention lies in the provision ofcontact-retaining means of the type indicated whereby a contact may beremoved, if necessary, from the connector part so as, for example, tocorrect a faulty connection to the connector part.

The above and further objects and novel features of the invention willmore fully appear from the following detailed description when the sameis read in connection with the accompanying drawings. It is to beexpressly understood, however, that the drawings are for purposes ofillustration only and not intended as a definition of the limits of theinvention.

In the drawings, wherein like characters refer to like parts throughoutthe several views,

FIG. 1 is a view taken partially in longitudinal axial section throughtwo aligned confronting parts of a separable electrical connector madein accordance with one embodiment of the invention, the two connectorparts being shown in position to be coupled together by axial movementtoward each other followed by a manipulation of the locking means, someof the parts being shown in side elevation, the respective connectorparts being shown with a set of two mating contacts, the contacts beingomitted at other locations in the connector parts for clarity ofillustration;

FIG. 2 is a view in end elevation of the connector part shown at theleft in FIG. 1, the view being taken in the direction from right to leftin FIG. 1;

FIG. 3 is a view in end elevation of the connector part shown at theright in FIG. 1, the view being taken in the direction from left toright in FIG. 1;

FIG. 4 is a schematic view partially in axial section and partially inside elevation of a pair of cooperating contacts in position to beimmediately engaged with each other, the figure particularlyillustrating the manner in which the contacts are accurately locatedaxially of their mounting means and are prevented from axialdisplacement with respect thereto during the operations of connectingand disconnecting the contacts;

FIG. 5 is a view on an enlarged scale of a portion of FIG. 4, the viewshowing the relationship between the retaining plate of the insert and acontact retained thereby;

FIG. 6 is a view in transverse section on an enlarged scale through amounted contact, the section being taken along line 66 of FIG. 4;

FIG. 6a is a view similar to FIG. 6, the view showing 3,125,395 PatentedMar. 17, 1964 the manner in which the contact-retaining plate of theinsert is distorted at the contact retaining passage therethrough duringthe contact mounting operation;

FIG. 7 is a somewhat schematic fragmentary view illustrating the mannerin which an assembled contact and Wire are mounted within a compositecontact locating and retaining insert assembly of the connector of theinvention, the view showing the parts at the beginning of thecontact-mounting operation;

FIG. 8 is a view similar to FIG. 7, but with the contact thrust intofully inserted position in the composite insert of the connector part bythe assembling tool;

FIG. 9 is a fragmentary view in perspective showing the manner ofengagement between the jaws of an assembling tool and a first embodimentof contact in accordance with the invention;

FIG. 10 is a view similar to FIG. 9, but showing the manner ofengagement between the jaws of the assembling tool and a secondembodiment of contact in accordance with the invention;

FIG. 11 is a view partially in longitudinal axial section and partiallyin side elevation of a tool which may be employed to disassemble, whennecessary, the contacts from the connector parts of the connector of theinvention;

FIG. 12 is an enlarged view partially longitudinal axial section andpartially in side elevation of the operative portion of the tool of FIG.11, the tool being adapted for the removal of a pin contact from theconnector of the invention, the tool being shown in position to beapplied to such pin contact;

FIG. 13 is a view in side elevation of the operative portion of the toolfor removing a socket contact from the connector of the invention;

FIG. 14 is a somewhat schematic fragmentary view illustrating theremoval of a pin socket from the connector of the invention, the viewshowing the start of such pin-removing operation; and

FIG. 15 is a view similar to FIG. 14, but showing the parts after thepin-removing tool has been applied to the pin and has been thrustrearwardly so as to disengage the pin from the retaining means thereforin the insert of the connector part.

The electrical connector of the present invention is particularlyadvantageous when it is employed with contacts which are connected totheir respective conductors such as wires by being crimped theretorather than soldered. In Herman Keller et al. US. Patent No. 3,028,776,there is disclosed and claimed a crimping tool for carrying out suchwire-and-contact-connecting operation. Such crimped connection has, ingeneral, proved to be more reliable than soldered connections, and ismore economically made. Such connection eliminates the tinning of thewire; such tinning is disadvantageous in that it tends to make thetinned end of the stranded wire rigid and thus easily broken in the zoneimmediately adjacent to the joint. Further, no source of heat, such as asoldering iron, is necessary to make the joints, and since each joint ismade before the contact is mounted in the connector part, the need forextremely painstaking work, required when wires are soldered to theclosely spaced solder wells of assembled contacts in connectors made inaccordance with the prior art is eliminated.

The electrical connector of the present invention is of suchconstruction that, after a joint has been made between the end of a wireand a contact, the contact and wire may then be readily mounted into apreviously assembled connector part including a shell having acontact-retaining insert therewithin. The contact and the insert of theconnector of the invention have interfitting formations thereon soconstructed and arranged that the contact may be thrust into its fullyinserted operative position by essentially straight line axial movementthereof, the contact being securely held in such position despiterepeated operations of engagement with and disengagement from a matingcontact. The construction of the insert and contact retaining formationsis preferably such that, when necessary, the contact may be removed fromthe connector part by an operation which is the reverse of the assemblyoperation. As a result of such preferred construction, errors in circuitconnections may be readily corrected without injury to the contact or tothe locating and retaining insert of the connector part. It is to beunderstood, however, that, within the broader aspects of the invention,the contacts need not be thus removable after having been mounted in theinsert.

Turning now to the drawings, there is shown in FIG. 1 a separableelectrical connector of the multi-contact type, both halves of suchconnector being made in accordance with the present invention. Theconnector half or part at the left, designated in the embodiment shown,is adapted to support and retain a plurality of socket contacts, one ofwhich is shown at 11. The connector part shown at the right in FIG. 1and generally designated 12, is adapted to support and retain aplurality of pin contacts, of which one is shown at 14. Connector parts10 and 12 are shown somewhat separated but aligned so that therespective socket and pin contacts carried thereby will be placed inmating relationship when connector parts 10 and 12 are advanced intooperative engagement. In the embodiment shown, the shells or housings ofthe connector parts, and the means for holding the connector parts inoperative engagement, are generally similar to those disclosed inHennessey and Swanson Patent No. 2,984,811.

Briefly, the connector part 10 has a tubular shell 15 having suitableannular recesses therein for mating with the forward portion of acomposite insert 19 which is retained within shell 15. The inner wall ofshell 15 also includes a conventional longitudinal extending key memherwhich extends into a shallow groove in the exterior of the compositeinsert, whereby accurately to orient the insert angularly with respectto shell 15. Connector part 12 has a generally similar shell 20 whichaccurately retains a composite insert member 21 therein in apredetermined position both lengthwise and angularly with respect toshell 20.

In the embodiment of the connector shown, connector part 12 is of thewall mounted type having a forwardly extending hood portion 22 which isdesigned telescopically to receive the forward portion 24 of shell 15.Hood 22 and portion 24- of shell 15 are accurately oriented angularlywith respect to each other by one or more interfitting splines 25 onportion 24 and interfitting grooves 26 on hood 22. Connector halves 10and 12 are retained together in operative position by an outer nutmember 27 rotatively mounted upon shell 15. Nut member 27 has threebayonet grooves 29 in its inner forward surface, such grooves receivingthe pins 39, shown in FIG. 3, projecting radially from the outer surfaceof hood 22. When the pins 30 are received in the forward ends of grooves29 and the nut 27 is turned in the proper direction (counterclockwise inFIG. 2), connector parts 10 and 12 are drawn strongly together by theaction of nut 27, the axial thrust from the nut being transmitted toshell 15 from flange 31, on the nut 2'7, through a bent annular leafspring 32 to a radially outwardly directed flange 34 on shell 15.

The embodiment of separable connector shown is adapted simultaneouslyeither to make or break the electrical circuits in a plurality of wires.Thus the inserts 19 and 21 of the respective connector parts eachcarries the same number of mating contacts. Such inserts are requiredaccurately to locate the respective contacts both as regards theirradial distance from the axis of the connector part and their spacingangularly about such axis, to locate the contacts accurately axially ofthe shell of the connector part, to maintain the contacts electricallyinsulated from each other, and to seal the outer or rear ends of thecontacts and the wires connected thereto from the atmosphere. In theconnector of the present invention such insert has the further functionof allowing the assembled contacts and wires connected thereto to beinserted into the previously assembled composite insert and connectorshell by an operation involving substantially only axial movement of thecontact relative to the insert and shell. In preferred embodiments ofthe connector, the configuration of the parts is such that the contactsmay also be removed, if necessary, by relative axial movement betweenthe contact and the connector shell and insert.

The composite inserts 19 and 21 are generally similar, differing only asto the axial length of the forward portions thereof and the contour ofthe portions of the passages through the insert which are located insuch forward portions. Taking insert 19 as typical, such insert has aforward, contact-locating portion 35, an intermediate contact-retainingplate 36, and a rear contact end conductor-sealing grommet 37. Forwardportion 35 of the insert is made of a relatively stiif rubber orrubber-like material, whereby accurately to locate the contacts, asexplained. Plate 36 is made of a relatively stiff but yieldableelectrical insulating material. In one embodiment of the invention,plate 36 is made of a molded resin such as nylon. The grommet 37 is madeof a rubber or rubber-like material of an intermediate durometer value,whereby the grommet may be readily deformed by a compressing means so asto seal it about the contacts and their wires.

As will be explained hereinafter, the parts of the composite insert arepreferably bonded to each other and to the connector shell prior to themounting therein of the contacts and their connected wires. Theconnector of the invention is designed to be sold in partiallydisassembled form: thus, as to the connector shown, the compositeinserts 19 and 21 will have been assembled within and bonded to theirrespective shells 15 and 2:"). The pin and socket contacts will not asyet have been mounted in the inserts, and the rear housing parts,including the grommet compressing sleeves and the conductor clampingmeans shown, will not have been mounted upon the shell parts 15 and 20.The final assembling of the parts, including the connection of thecontacts to conduit wires and the mounting of the thus assembledcontacts and wires in the connector parts, is carried out by theconsumer.

Thus in the wiring of an aircraft, for example, the worker will cut thevarious wires to length and mount the contacts on the ends thereof insitu, following which he will insert the contacts and connected wiresinto the respective connector parts, after having telcscoped over theconduits or wires the appropriate elements which will ultimately beassembled with the shells to lie rearwardly thereof. After the contactshave been mounted in their respective axial passages in the insert 19,connector part 10 will be completed by advancing nut 27 into place, bydisposing grommet compressing sleeve 39 over the rear end of the grommet37, and by screwing home the rear portion 40 of the housing of connectorpart 10, whereby to compress the grommet radially inwardly upon thecontacts and the wires extending therethrough. Finally, the rubber clampgrommet 41 is slid into place about the grouped conductor wires, and isheld clamped against the wires by the split clamping means 42 attachedto arms 44 projecting rearwardly from housing part 40.

The assembling of connector part 12 is carried out in a similar manner.Since the parts at the rear of the shell of connector part :12 aresubstantially identical with those at the rear of connector part 10,they are designated by the same reference characters but with an addedprime.

The manner of location and retention of contacts 11 and 14,respectively, in connector parts 10 and 12 will be more fully understoodby a consideration of the shapes of the unoccupied passages in therespective inserts, shown substantially in their relaxed configurationsin FIG. 1, with the shapes of the contacts 11 and 14 which such passagesare to accommodate. The portion 45 of such passage which lies in forwardinsert portion 3 has such configuration as generally snugly to embracethe forward socket portion 18 of contact 1 1 and to provide an openingthrough which the pin 13 may be inserted into the socket. The passage 45thus has a radially inwardly projecting annular portion which engagesthe shank of contact 1 1 rearwardly of the socket. The plate 66 has acircular cylindrical hole 46 therein in alignment with each passage 45,the relaxed diameter of such hole 46 slightly exceeding the maximumdiameter of any portion of the socket 18, so that the socket may befreely inserted into the insert through hole 46 in the plate.Immediately forwardly of plate 36, passage '45 in forward insert 34 hasa relaxed shape which is frusto-conical, and which converges in aforward direction, the rear, larger end of such frusto-conical portionsomewhat exceeding the diameter of hole 46.

The portion of the passage through the insert in the rear grommetportion 37 is designated 47. Passage 47 has .a relaxed diameterthroughout its length such as to pass the contact 11 fairly freelytherethrough. Adjacent its outer end, grommet 37 has an inwardlyprojecting annular sealing flange portion 38 which is adapted to besqueezed tightly about the wire 49 connected to contact 11 when theparts are fully assembled as shown in FIG. 1. As above explained,grommet 37 is made of relatively soft rubberlike material which may bereadily temporarily distorted when contact 11 is being assembled ordisassembled therethrough.

The same considerations exist in the design of the configuration of thepassage through insert 2 1 in connector part 12. Thus the portion of thepassage in forward insert part 35, here designated 45", has such shapeas snugly to embrace pin contact 14, including the forward enlargedportion 50 thereon, and to allow the pin 13 to protrude forwardly ofinsert portion 3 5. The hole 46' in contact retaining plate 36 is ofsuch relaxed diameter as freely to pass enlargement 50 on pin contact 14 there-through. The portion of the passage in grommet 37' is generallythe same as that in grommet 37, being of such diameter as fairly freelyto pass the pin contact therethrough, and having an inwardly projectingannular portion 3-8 adja cent its rear end [which is sealingly pressedagainst the wire 49, connected to contact 14, when the parts areassembled as shown in FIG. 1.

The manner of connection of the wires to the respective contacts, and ofthe holding of the contacts in their respective inserts are generallythe same. These features will be understood more fully uponconsideration of FIGS. 4, 5, and 6. As there shown, the rear ends of thecontacts are provided with ferrules, designated 51 for contacts 11 and 51' for contact 14, into which the ends of the respective wires 49 and49' are inserted. The fully inserted condition of the wires relative tothe ferrules may readily be detected by the assembler by looking intothe transverse passages 54 through the contacts at the forward end ofthe ferrules. The wires are electrically connected to the contacts andfirmly secured thereto by the crimping of the ferrules so as to formopposing indentations 5 2, 5-2 in the side walls thereof. Such crimpingof the contacts upon the wires may conveniently be performed by the useof a crimping tool such as that described and claimed in the abovereferred to Keller et al. Patent No. 3,028,776.

The manner of retention of contacts .11 and 14 against axial movementrelative to their respective inserts are the same in the embodiment ofconnector shown; a detailed description of the means for retaining acontact in insert 19 of connector part will suffice.

Immediately forwardly of ferrule -51, contact 11 has two axially spacedplate-engaging formations thereon which cooperate with the retainingplate 36 stably to retain the contact in a predetermined axial positionrelative to the connector part in which it is mounted. In the embodimentshown, the contact-retaining means also selectively allows thewithdrawal of the contact when it becomes necessary, for example, tocorrect a faulty circuit. The rear contact-retaining formation on thecontact, designated 56, is the form of an abrupt, right-angled annularshoulder having a diameter appreciably exceeding the diameter of hole 46in plate 36. Shoulder 56, when in engagement with the rear surface ofplate 36-, definitely locates contact 11 axially and prevents itsfurther forward travel after it has been fully mounted within theinsert. The second, forward formation on the contact, generallydesignated '57, is made up of two oppositely facing ramplike portionswhich function momentarily to deform the plate 36 in the vicinity ofhole 46 therethrough both during the insertion of the contact intooperative position within the insert and its withdrawal therefrom.

The forward portion of the forward formation is in the form ofdiametrically opposed frusto-conical surfaces 59 which converge in aforward direction to a root portion on the body of contact '11, suchroot portion being of somewhat smaller diameter than the diameter d ofhole 46. Surfaces '59 are separated by the opposite flat surfaces 62.The rear, larger diametered ends of frustoconical portions 59 join witha short circular cylindrical zone 60, which has a diameter D appreciablyexceeding the relaxed diameter of hole 46 in plate 36. Forwardly ofshoulder 56 the body of contact 1!]. is provided with an axially shortcircular cylindrical seat 55 having a diameter d which is somewhat lessthan the diameter d of hole 46. The zone of the body of contact 11between the rear end of surface '60 and the forward end of seat 55 isformed mainly of a rearwardly convex toroidal surface 61 which mergessmoothly with surface 60 at its forward end and is connected at its rearend to seat 55 through a short ra-diuse-d fillet.

In the embodiment of connector shown, the plate 36 preferably has athickness which lies within the range T--T (FIG. 5) that is, when thecontact is installed in the plate the forward edge of the plate 3 6 athole 46 preferably lies upon toroidal surface 611. With suchconstruction, surface 61 constantly resiliently deforms resilient plate36 so that the plate constantly urges the contact 11 forwardly, so thatshoulder '56 is thrust against the rear of the plate, thereby accuratelylocating the contact in an axial direction. Plate 36 has suificientresilience that during installation of the contact in the plate and itswithdraw-a1 therefrom, the hole 46 is momentarily deformed, generally asshown at '46 in FIG. 6a. The presence of the opposite flatted zones 62at the location of means 57 allows the hole 46 to be generally deformedinto an oval; after means 57 has passed plate 36, the hole 46 thereingenerally resumes its circular shape, except for the portion of itssidewall overlying surface 61.

In accordance with the invention, should it not be desired that thecontacts shall be removable, or at least readily removable, from theinsert, the plate 36 can be made of a thickness such that it snugly fitswithin seat 55 and does not overlie curved surface 61 much, if at all.Such construction accurately locates the contact in an axial direction,but makes it increasingly difficult to retract the contact from plate36, because of the increased steepness of the angle at which the forwardedge of plate 36 initially engages curved ramp surface 61.

FIGS. 7 and 8 illustrate the operation of mounting a pin contact 14,which has been crimped to a wire 49, in connector part 12. In carryingout such operation, there is conveniently employed an assembling tool 65which closely resembles a pair of needle-nosed pliers. The forward endsof the jaws of tool 65 are in the form of thin axially extending shells66 which, when closed, present substantially a circular cylindricalpassage longitudinally between them. Portions 66 of the jaws are soconstructed that, when closed upon the rear ferrule end of the contact14, they firmly grip the contact and maintain it from deflection. Theouter diameter of jaw portions 66, when such portions are closed uponthe ferrule 51 of the contact, does not appreciably exceed the diameterof shoulder portion 56 of the contact. Rearwardly of gripping portion 66the forward legs of the tool are relieved from each other to form anelongated space 67 which somewhat exceeds the diameter of wire 49'.

With the contact 14 gripped by tool 65 in the manner shown in FIG. 7,and with wire 49 extending rearwardly from gripping portions 66 of thetool and thence laterally from space 67, the tool and its gripped wireand contact are advanced axially of connector part 12 with the contactin alignment with the proper passage 47 in the insert thereof. Aftercontact 13 has been initially inserted into passage 4-7, continuedadvance of the contact eventually brings the parts into the positionshown in FIG. 8, wherein the forward contact-retaining formation 57 oncontact 14 has snapped through the hole 46' in retaining plate 36'. Whensuch fully inserted position of the contact has been reached, the tool65 may be retracted merely by pulling it rearwardly of the connectorpart 12, following which the grommet 37' contracts into snug engagementwith the rear end of contact 14 and with the wire 49' crimped thereto.

In FIG. 9 the forward gripping portions 66 of the tool 65 are shown inthe process of being engaged with the ferrule of a socket contact 11.Ordinarily the pin and socket contacts of one size of connector are somade that the same assembling tool 65 may be employed to assemble boththe pin and the socket contacts thereof. Thus the ferrule 51 of socketcontact 11 will have substantially the same diameter as ferrule 51' ofpin contact 14.

In some instances, particularly when the wire 49 is of small diameter,there may be employed pin and socket contacts which have a second, rear,ferrule which may be crimped about the end of the insulation on thewire. FIG. 10 shows an alternative socket contact 11' of suchconstruction. Contact 11, in addition to the wire-engaging ferrule 51,has a second, rear, ferrule 69 which is clenched about the end of theinsulation on wire 49. In installing contacts such as contact 11, thegripping portions 66 of an assembling tool are preferably clampinglyengaged with the rear ferrule 6% in the manner indicated in FIG. 10.

As indicated above, in its preferred embodiment the electrical connectorof the present invention incorporates contact retaining means of suchcharacter that the contacts may be removed from their operative positionwithin the insert of the connector part without injury to either thecontacts or the insert. In FIGS. ll-lS, inclusive, there are illustratedcontact-removing tools which may conveniently be used in the manner ofremoval of typical contacts made and retained in accordance with theinvention.

The contact-removing device shown, generally designated 74, is in theform of a hollow handle 75 having means on its forward end for theremovable mounting of the appropriate contact-removing tool 76. Theother contact removing tools are conveniently stored within the handle.In FIGS. 11 and 12 the tool 76 there shown is for the removal of a pincontact from a connector part, and thus has a forward portion 77 in theform of a thin axially directed tube which accurately receives thecontact pin 13 within it; the outer diameter of tube 77 does notappreciably exceed the diameter of the enlargement St) on the contactpin.

The tool 79, which may alternatively be mounted upon the forward end ofhandle 75, as shown in FIG. 13, is in the form of an elongated pin witha forward axially extending end 89 having a diameter substantially thatof the contact pin. End 80, which is designed to be received y... insocket 18 of a socket c nlact 11, has a length which somewhat exceedsthe length of the passage in socket 18, so that the socket-removingthrust is exerted upon the inner end of the passage in the socket. Tool'79 has a rear enlarged shank 31 which aids in guiding tool 79 withinthe insert in the connector part, once portion 80 of the tool has beeninserted within socket 18.

In FIGS. 14 and 15 there is somewhat schematically illustrated theoperation of removing a pin contact 14 from a connector part 12. Theproper tool 76 is applied to handle 74, and the tubular portion 77 oftool '76 is now advanced toward pin 13 in alignment therewith. Aftertubular portion 77 has been telescoped over the projecting end of pin13, continued movement of portion 77 to the left causes it to penetrateWithin the passage in the insert 21 and to engage the enlargement 50 onthe contact pin, and thereafter causes the contact 14 to move to theleft (FIG. 14) and the forward contact-retaining formation 57' thereonto snap rcarwardly through the hole 46' in plate 36. The diameter oftool portion 77 is somewhat less than that of hole 46', so that the toolmay then freely be thrust toward the left, as shown in FIG. 15,substantially completely to remove the contact from the insert 21.

The assembling of the shell of the connector part and the compositecontact locating and retaining insert may conveniently be carried out asfollows. The connector shell, which is ordinarily made of metal, isdegreased as by being subjected to a suitable solvent. The rear face ofthe forward portion of the insert (for example, 35 in connector part 10)and the forward face of the grommet 37 are roughened as by being sandedon a suitable abrading surface. Both sides of the contact-retainingplate 36 are roughened as by either being sanded or blasted withabrasive. All such roughened surfaces should be flat to facilitateproper binding. The rear face of the forward insert part, in addition tobeing flat, must be accurately located so as to lie accurately in apredetermined position axially of the connector shell when parts arefully assembled.

After being thoroughly cleaned, the parts are bonded together. Aconvenient and satisfactory method for securing such bonding is asfollows. A uniform coating of a suitable adhesive is applied to themating diameters of the forward insert portion (35), the metal shell,the rear face of the forward portion of the insert, the forward face ofthe grommet (37), and both sides of the contact retaining plate (36).All of such parts are now baked for a short time at a relatively lowtemperature, so as preliminarily to set the adhesive. The forwardportion of the insert is now snapped into place in the shell, followingwhich the shell with the forward portion of the insert 35 therein isbaked to adhere such parts together. After such assembly is returned toroom temperature, a fresh coating of adhesive is applied to both sidesof plate 36, the adhesive coatings on the rear face of the forwardinsert part 35 and the forward face of grommet 37 are reactivated, as bybeing treated with a suitable solvent.

The shell with insert part 35 assembled therein is now mounted upon asuitable alignment fixture having a base plate and a plurality ofalignment pins projecting vertically therefrom, there being one such pinfor accurately fitting within each of the passages in insert portion 35,plate 36, and grommet 37. Plate 36 is now mounted upon the upwardlyprojecting pins of the fixture, and the grommet 37 is then superimposedupon plate 36 and held thereagainst under light pressure, as by asuitable clamping means cooperating with the alignment fixture. Thefixture, with the connector parts mounted thereon as described, is nowcharged into a suitable oven where the parts are baked at suchtemperature and for such length of time as to complete the bonding ofinsert portion 35 to the shell, and to bond the plate 36 to insertportion 35 and to grommet 37 completely over the interfaces between suchparts.

For the purposes of illustration there are given below the salientdimensions of the parts retaining a contact of a typical electricalconnector made in accordance with the invention. The contact, which isof the size known commercially as Size 16, has a maximum diameter in itsforward portion (of element 50 if it is a pin contact; of socket 18 itit is a socket contact) of .125 in. Zone 60 has a diameter of .135 in.;surface 59 makes an angle a of 69 with a plane transverse to the axis ofthe contact. Seat 55 has a diameter of .120 in., hole 46 in plate 36 hasa diameter of .131 in., and shoulder 56 has a diameter of .141 in. Theintersection of surfaces 59 and 60 lies .078 in. from shoulder 56 alongthe axis of the contact. The elements of surface 61, which lie in axialplanes through the contact, are portions of circles tangent to surface60, and extend down substantially to the level of seat 55 except for theinterposed fillet therebetween, such fillet having a maximum radius of.004 in.

The plate 36, which in the described embodiment is made of molded nylonsold under the trade-name Zytel 101 nylon, has a thickness which mayrange from (FIG. T=.060 in. to T'=.068 in. As shown in such figure, whenthe plate 36 has its minimum permissible thickness its forward edgeapproximately overlies the midpoint of surface 61. When plate 36 has itsmaximum permissible thickness, its forward edge approximately overliesthe transverse line of tangency between surfaces 61 and 60.

Many of the advantages of the electrical connector of the presentinvention will have become apparent in the foregoing description. Thereare, of course, other advantages; among them are the fact that the novelcontactretaining means and the preferred novel means connecting thecontacts to their lead Wires add little if anything to the spacerequirements of the contacts of electrical connectors of the prior art.Consequently halves of electrical connectors in accordance with thepresent invention may readily be made of such dimensions as to matesatisfactorily with complementary connector halves made in accordancewith the prior art.

Although only one embodiment of the invention has been illustrated inthe accompanying drawings and described in the foregoing specification,it is to be especially understood that various changes, such as in therelative dimensions of the parts, materials used, and the like, as wellas the suggested manner of use of the apparatus of the invention, may bemade therein without departing from the spirit and scope of theinvention as will now be apparent to those skilled in the art.

What is claimed is:

1. An electrical connector comprising in combination a substantiallyrigid contact supporting plate having a passage therethrough and anelongated metal contact extending through said passage, said contacthaving a first enlarged portion forming a shoulder engaging one face ofsaid plate around said passage to hold said contact against movement inone direction relative to said plate and having a second enlargedportion axially spaced from said first portion forming a taperingshoulder facing said first-named shoulder and engaged intermediate theradial extremities thereof by said plate at the junction of the otherface of the plate with the wall of said passage to restrain said contactagainst movement in the other direction relative to said plate, thatportion of said contact between said shoulders being of smallertransverse section than said passage and said contact being rigid and soconstructed in the region of said second enlarged portion that theperipheral shape and dimensions of said second enlarged portion areunaffected by compressive radial forces applied thereto.

2. An electrical connector comprising in combination a contactsupporting plate having a passage therethrough, said plate beingsubstantilly rigid but sufiiciently resiliently pliable in a radialdirection to permit slight deformation of said passage in response tosubstantial radial pressure against diametrically opposed Wall portionsthereof, and a rigid elongated metal contact extending through saidpassage, said contact having a first enlarged portion forming atransverse shoulder engaging one face of said plate around said passageto hold said contact against movement in one direction relative to saidplate and having a second enlarged portion forming a tapering shoulderfacing said transverse shoulder, said tapering shoulder beingresiliently gripped intermediate the radial extremities thereof by saidplate adjacent the end of said passage to restrain said contact againstmovement in the other direction relative to said plate, that portion ofsaid contact between said shoulders being spaced radially inward fromthe walls of said passage, and said second enlarged portion having apermanent, unyielding peripheral shape adapted to deform said passageand thereby set up and maintain tension in the plate around saidpassage, whereby the plate exerts a radially directed gripping force onsaid tapering shoulder.

3. An electrical connector as defined in claim 2 wherein said secondenlarged portion on the contact forms a second tapering shoulder facingaway from said transverse shoulder whereby said second portion may bepassed through said passage upon deformation of the latter in responseto substantial force effecting longitudinal movement of said contact insaid one direction.

4. An electrical connector comprising in combination a substantiallyrigid but slightly resiliently deformable contact supporting platehaving a passage therethrough and an elongated metal contact extendingthrough said passage, said contact having a transverse shoulder engagingone face of said plate at one end of the passage to hold said contactagainst movement in one direction relative to said plate and having anenlarged portion axially spaced from said transverse shoulder saidenlarged portion being rigid and permanently, unyieldingly, peripherallyshaped to enlarge the relaxed transverse dimensions of the passage in atleast one sector while permitting contraction of the transversedimensions of the passage in an adjacent sector, whereby the plate istensioned around said passage to exert a radially directed grippingforce against said enlarged portion of the contact, said plate adjacentthe other end of said passage surrounding and resiliently gripping apart of said enlarged portion having a transverse dimension greater thanthe corresponding relaxed dimension of said passage, that part of saidcontact between said shoulder and said enlarged portion being radiallyinwardly spaced from the walls of the said passage.

5. An electrical connector comprising a tubular housing, an electricallyinsulating insert member secured within said housing, said insert membercomprising a forward, contact-locating portion made of resilientrubber-like material, a contact-retaining plate made of substantiallyrigid but slightly resiliently deformable material positioned rearwardlyof the forward portion, the forward portion and the plate beingintimately bonded to each other over substantially the entire extent oftheir interfaces, and means rearwardly of the plate thrusting the platein a forward direction against the forward portion of the insert member,said insert member having a passage longitudinally therethrough, and anelongated contact having a substantial part of its length located withinsaid passage, said contact having axially spaced formations thereoncooperating with the forward and rear edges of that portion of thepassage located in the plate through which the contact extends to retainthe contact from appreciable longitudinal movement relative to theinsert member during normal operations involving connecting anddisconnecting the connector, the forward formation on the contact beingsuch as to allow such forward formation to be snapped through theportion of the passage in the plate in the forward direction and saidforward formation being resiliently gripped by said plate only at theforward end of the portion of the passage in said plate to yieldablyretain the contact against rearward movement relative to the insertmember.

6. An electrical connector comprisng a tubular shell, a compositeelectrically insulating insert member secured within said shell, saidinsert member comprising a forward, contact-locating portion made ofresilient rubberlike material, an intermediate contact-retaining platemade of substantially rigid but resiliently deformable material, and arear contact-sealing grommet made of resilient rubher-like material,said insert member having a passage longitudinally therethrough, and anelongated contact having a substantial part of its length located withinsaid passage, said contact having axially spaced radially enlargedformations thereon cooperating with the forward and rear edges of thatportion of the passage which is located in the plate and through whichthe contact extends to retain the contact from appreciable longitudinalmovement relative to the insert member during normal operationsinvolving connecting and disconnecting the connector, the forwardformation on the contact being such as to allow such forward formationmomentarily to resiliently deform the plate in the vicinity of theportion of the passage through the plate and thus to be snapped throughthe plate by thrusting the contact in the forward direction relative tothe plate and said forward formation, at a zone spaced less than thethickness of said plate from the rearward formation, having a transversedimension greater than the corresponding relaxed dimension of saidportion of the passage in the plate, whereby said forward formation isresiliently gripped by said plate in the zone of the forward end of saidportion of the passage.

7. An electrical connector comprising a tubular shell, a compositeelectrically insulating insert member secured within said shell, saidinsert member comprising a relatively stiff forward, contact-locatingportion made of resilient rubber-like material, an intermediatecontact-retaining plate made of substantially rigid but slightlyresilient molded resin, and a rear relatively soft, contact-sealinggrommet made of resilient rubber-like material, the forward portion, theplate, and the grommet being intimately bonded together oversubstantially the entire extents of their interfaces, said insert memberhaving a plurality of passages longitudinally therethrough, andelongated contacts located within said passages, each of said contactshaving axially spaced radially enlarged formations thereon cooperatingwith the forward and rear edges of a hole in the plate through which thecontact extends to retain the contact from appreciable longitudinalmovement relative to the insert during normal connecting anddisconnecting operations, the forward formation on the contact having aramp-like configuration to allow such forward formation momentarily todeform the plate in the vicinity of the hole and thus to be snappedthrough the hole in the plate by thrusting the contact in the forwarddirection relative to the plate and said forward formation having aportion within the forward end of said hole which has a transversedimension greater than the corresponding relaxed dimension of the holewhereby said forward formation is permanently gripped by said plate toyieldably retain the contact against rearward movement relative to theinsert member, said contacts having substantial parts of their lengthslocated within the composite insert member, the grommet beingresiliently deformable to allow the insertion of the contactstherethrough.

8. An electrical connector comprising in combination a contactsupporting plate having a passage therethrough, said plate beingsubstantially rigid but sufficiently resiliently pliable in a radialdirection to permit slight deformation of said passage in response tosubstantial radial pressure against circumferentially spaced wallportions thereof, and an elongated metal contact extending through saidpassage, said contact having a first enlarged portion forming atransverse shoulder engaging one face of said plate around said passageto hold said contact against movement in one direction relative to saidplate and having a second enlarged portion forming a tapering shouldercomprising circumferentially spaced sectors of a convex toroidal surfacefacing said transverse shoulder and resiliently gripped intermediate theradial extremities thereof by said plate adjacent the end of saidpassage to restrain said contact against movement in the other directionrelative to said plate, that portion of said contact between saidshoulders being spamd radially inward from the walls of said passage.

9. An electrical connector comprising a tubular shell, a compositeelectrical insulating insert member secured within said shell, saidinsert member comprising a forward, contact-locating portion made ofresilient rubberlike material, an intermediate contact-retaining platemade of substantially rigid material capable of slight resilientdeformation and a rear contact-sealing grommet made of resilientrubber-like material, said forward portion and the grommet intimatelycontacting opposite faces of the plate over substantially the entireextents of their interfaces and said insert member having at least onepassage longitudinally therethrough, and an elongated contact locatedwithin said passage, said contact having axially spaced radiallyenlarged formations thereon cooperating with the forward and rear edgesof a hole in the plate through which the contact extends to retain thecontact from appreciable longitudinal movement relative to the insertduring normal connecting and disconnecting operations, the forwardformation on the contact being longitudinally tapered and of oblongtransverse section having a major axis of slightly greater length and aminor axis of less length than the corresponding relaxed dimensions ofsaid hole such as to allow such forward formation momentarily to deformthe plate in the vicinity of the hole and thus to be snapped through thehole in the plate by thrusting the contact in the forward directionrelative to the plate.

10. An electrical connector as defined in claim 9 wherein said forwardformation has a rearwardly tapering portion at least partiallysurrounded by said plate and engaged by said plate at the junction ofthe forward face of the plate with the wall of said hole.

11. An electrical connector comprising a tubular shell, a compositeelectrically insulating insert member secured within said shell, saidinsert member comprising a relatively stiff forward, contact-locatingportion made of resilient rubber-like material, an intermediatecontactretaining plate made of substantially rigid material capable ofslight resilient deformation and a rear relatively soft, contact-sealinggrommet made of resilient rubber-like material, said forward portion,the plate, and the grommet being bonded together along their interfaces,said insert member having at least one passage longitudinallytherethrough, and an elongated contact located within said passage, saidcontact having axially spaced radially enlarged formations thereoncooperating with the forward and rear edges of a hole in the platethrough which the contact extends to retain the contact from appreciablelongitudinal movement relative to the insert during normal connectingand disconnecting operations, the forward formation on the contacthaving circumferentially spaced ramp-lil e configurationscircumferentially joined by reduced portions to allow such forwardformation momentarily to resiliently deform the plate in the vicinity ofthe hole and thus to be snapped through the hole in the plate bythrusting the contact in the forward direction relative to the plate,said contact having a substantial part of its length located within thecomposite insert member, the grommet being resiliently deformable toallow the insertion of the contact therethrough,

12. An electrical connector comprising a tubular shell, a compositeelectrically insulating insert member bonded to said shell, said insertmember comprising a relatively stiff forward, contact-locating portionmade of resilient rubber-like material, an intermediatecontact-retaining plate made of substantially rigid but slightlyresiliently deformable material and a rear, relatively softcontactsealing grommet made of resilient rubber-like material, saidinsert member having at least one passage longitudinally therethrough,and an elongated contact having a substantially part of the lengththereof located within said passage, said contact having axially spacedradially enlarged formations thereon cooperating with the forward andrear edges of a hole in the plate through which the contact extends toretain the contact from appreciable longitudinal movement relative tothe insert during normal connecting and disconnecting operations, theforward formation on the contact having a forward ramp-likeconfiguration to allow such forward formation momentarily to deform theplate in the vicinity of the hole and thus to be snapped through thehole in the plate by thrusting the contact in the forward directionrelative to the plate and having a rear ramp-like configurationextending into said hole and engaged intermediate its radial extremitiesby the plate at the forward end of said hole.

13. An electrical connector comprising in combination a substantiallyrigid contact supporting plate having a passage therethrough and anelongated metal contact extending through said passage, said contacthaving a first enlarged portion forming a shoulder engaging one face ofsaid plate around said passage tohold said contact against movement inone direction relative to said plate and having a second enlargedportion axially spaced from said first portion forming a taperingshoulder facing said first-named shoulder and engaged intermediate theradial extremities thereof by said plate at the junction of the otherface of the plate with the wall of said passage to restrain said contactagainst movement in the other direction relative to said plate, thatportion of said contact between said shoulders being of smallertransverse section than said passage and said second enlarged portionhaving some transverse dimensions thereof smaller than the correspondingtransverse dimensions of said passage, whereby said second enlargedportion may be passed through said passage upon deformation of thelatter in response to substantial force effecting longitudinal movementof said contact in said passage.

14. An electrical connector comprising a tubular shell, a compositeelectrically insulating insert member bonded to said shell, said insertmember comprising a relatively stitf forward, contact-locating portionmade of resilient rubber-like material, an intermediatecontact-retaining plate made of relatively stiff but elasticallydeformable molded resin and a rear, relatively soft, contact-sealinggrommet made of resilient rubber-like material, said insert memberhaving a passage longitudinally therethrough, and an elongated contacthaving a substantial part of its length located within the said passagein the composite insert member, said contact having axially 14 spacedradially enlarged formations integral therewith and cooperating with theforward and rear edges of a hole in the plate through which the contactextends to retain the contact from appreciable longitudinal movementrelative to the insert during normal connecting and disconnectingoperations, the rear formation comprising an abrupt annular shoulderextending substantially around the body of the contact and the forwardformation having two similar diametrically oppositely extendingenlargements on the contact body, each of such enlargements havingramp-like configurations facing in opposite axial directions from thezone of greatest radial dimension of said enlargements to allow suchforward formation momentarily to deform the plate in the vicinity of thehole, whereby the contact may be snapped into and out of operativeengagement with the contact-retaining plate.

15. An electrical connector as defined in claim 14, wherein theforwardly facing ramp-like configurations are parts of the frustum of aforwardly converging cone, the hole in the plate is round, the forwardlyand rearwardly facing ramp-like configurations of each said enlargementare axially aligned, and said enlargements are circumferentiallyseparated by zones of reduced diameter on the body of the contact.

16. An electrical connector as defined in claim 14, wherein apredominant part of the zone of the contact body between said enlargedformations thereon is round and has a diameter at least somewhat lessthan the relaxed diameter of the hole in the contact-retaining plate.

17. A connector as defined in claim 14, wherein the rearwardly facingramp-like configurations are in the form of rearwardly convex portionsof a torus.

18. A connector as defined in claim 14, wherein the distance between theforward and rear formations on the contact body is so related to thethickness of the plate that when the shoulder on the contact engages therear edge of the hole in the plate, the forward portion of the sidewallof such hole partially overlies said rearwardly facing ramp-likeconfiguration of the forward formation.

References Cited in the file of this patent UNITED STATES PATENTS1,518,733 Eckstein Dec. 9, 1924 1,933,592 Hubbell Nov. 7, 1933 2,173,668Smith Sept. 19, 1939 2,383,926 White Aug. 28, 1945 2,419,018 Gudie Apr.15, 1947 2,429,585 Rogoif Oct. 21, 1947 2,563,713 Frei et al Aug. 7,1951 2,563,762 Uline et al Aug. 7, 1951 2,619,515 Doane Nov. 25, 19522,745,075 Simpkins et al May 8, 1956 2,877,441 Narozny Mar. 10, 19592,881,406 Arson Apr. 7, 1959 2,896,186 Hardmark July 21, 1959 2,903,670Sitz Sept. 8, 1959

1. AN ELECTRICAL CONNECTOR COMPRISING IN COMBINATION A SUBSTANTIALLYRIGID CONTACT SUPPORTING PLATE HAVING A PASSAGE THERETHROUGH AND ANELONGATED METAL CONTACT EXTENDING THROUGH SAID PASSAGE, SAID CONTACTHAVING A FIRST ENLARGED PORTION FORMING A SHOULDER ENGAGING ONE FACE OFSAID PLATE AROUND SAID PASSAGE TO HOLD SAID CONTACT AGAINST MOVEMENT INONE DIRECTION RELATIVE TO SAID PLATE AND HAVING A SECOND ENLARGEDPORTION AXIALLY SPACED FROM SAID FIRST PORTION FORMING A TAPERINGSHOULDER FACING SAID FIRST-NAMED SHOULDER AND ENGAGED INTERMEDIATE THERADIAL EXTREMITIES THEREOF BY SAID PLATE AT THE JUNCTION OF THE OTHERFACE OF THE PLATE WITH THE WALL OF SAID PASSAGE TO RESTRAIN SAID CONTACTAGAINST MOVEMENT IN THE OTHER DIRECTION RELATIVE TO SAID PLATE, THATPORTION OF SAID CONTACT BETWEEN SAID SHOULDERS BEING OF SMALLERTRANSVERSE SECTION THAN SAID PASSAGE AND SAID CONTACT BEING RIGID AND SOCONSTRUCTED IN THE REGION OF SAID SECOND ENLARGED PORTION THAT THEPERIPHERAL SHAPE AND DIMENSIONS OF SAID SECOND ENLARGED PORTION AREUNAFFECTED BY COMPRESSIVE RADIAL FORCES APPLIED THERETO.